The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.
Transmission Control Protocol (“TCP”) is the dominant application layer protocol that is presently used in internetworking. The performance and throughput of TCP-based applications is reflected in values of connection-level metrics, such as delay, round trip time (“RTT”) and packet loss. Current technology tracks TCP streams in a stateful manner and can allow an external individual or program to extract the RTT of flows. Programs such as “tcpdump” and “wireshark” may be used to tap network traffic, capture packets, organize the packets into TCP call-flows that have coordinated sets of segments such as SYN, SYN-ACK, ACK, and FIN segments; based on displays of these segments, RTT can be calculated. These packet capturing tools are often enabled at TCP end-hosts or as a bump in the wire inside the network. However, as networked systems become larger and more complex, containing many more nodes and servers, calculating RTT or hop-wise delays for all types of IP traffic becomes extremely complicated (n-squared problem) and resource-heavy since it involves maintaining the TCP state using the aforementioned methods. In particular, computing these performance metrics at line traffic speed becomes challenging.